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Kun Guo YANG Rui Mao HUA* Hai WANG Bo Qing XU* Department of Chemistry Tsinghua University Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Beijing Department of Chemistry Chemical Engineering Guangxi Normal University Guilin 《中国化学快报》2005,16(4)
Diphenylmethane and substituted diphenylmethane are important compounds forsynthesis chemistry as well as industrial chemistry. These compounds are easilysynthesized by the benzylation of aromatic compounds with benzyl chloride or benzylalcohol catalyzed by homogeneous acid catalysts, such as AlCl3, FeCl3, H2SO4, HF andBF3. However, these catalytic systems are highly corrosive, and usually proceed withlow selectivity. In addition, they are less satisfactory from the environmen… 相似文献
23.
Li Jing FANG Jin Chun CHEN Guo Jun ZHENG Yu Kun GUAN Yu Lin LI* State Key Laboratory of Applied Organic Chemistry Institute of organic chemistry Lanzhou University Lanzhou 《中国化学快报》2004,(11)
The eudesmane derivative, (-)-10-epi-α-cyperone 1, is widely used as a chiral starting material for the synthesis of other fused-ring sesquiterpenes1. The first synthetic work was reported by Howe and co-workers via condensation of (+)-dihydrocarvone 2 with 1-diethylaminopentan-3-one methiodide in 32% yield2. Previously, our group reported the synthesis of compound 1 by treating ketone 2 with ethyl vinyl ketone (EVK) directly under different conditions1a, but the yields were not satisfacto… 相似文献
24.
Xiao Long WANG Jian Peng FENG Xin Gang XIE Xiao Ping CAO* Xin Fu PAN* Department of Chemistry & State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2004,(9)
Aiphanol was isolated from the seeds of Aiphanes aculeate Willd. (Arecaceae) collected in Peru and was reported to exhibit significant inhibitory activities against cyclooxyge- nases-1 and -2. The structure of aiphanol was elucidated by spectroscopic methods as an unprecedented stilbenolignan skeleton in which a stilbene moiety is linked to a phenylpropane unit through a dioxane bridge1. In our previous works the synthetic approach to 1,4-benzodioxane lignans were achieved2. Since aiphanol… 相似文献
25.
~~Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide~~ 相似文献
26.
Juan Huang Jian Wei Wang Tao Gong Zhi Rong Zhang *Key Laboratory of Drug Targeting Ministry of Education West China School of Pharmacy Sichuan University Chengdu China 《中国化学快报》2007,(3)
To enable insulin as multi-drug carrier, we designed and synthesized dendritic linker molecule bearing three 5-Fluorouracil residues at the branch ends. The new conjugate showed excellent water solubility. The stabilities under different conditions were investigated. The results showed that the conjugate was a potential prodrug to release free 5-Fu. 相似文献
27.
氢气以其清洁无污染、燃烧值高等优点成为未来最具潜力的可再生能源之一,而清洁生产氢气的最佳选择之一即为裂解水. 利用太阳能模拟光合作用实现水的全分解产生氢气和氧气是目前最为理想的能源转化方式,并且已经引起了众多研究者的关注. 水分解的半反应之一--水氧化反应由于其过程复杂,一直是制约水分解的瓶颈. 所以寻找高效、稳定的水氧化催化剂便成为了突破该瓶颈的关键. 多金属氧酸盐是一类以前过渡金属氧簇为基本单元形成的多金属氧簇化合物. 由于多金属氧酸盐在物理、化学性质方面具有无法比拟的特性,使得其在催化、药物、纳米科技和材料科学等方面已被广泛地应用. 多金属氧酸盐的全无机配体可很好地抵御水氧化反应的强氧化性环境,故将其作为水氧化催化剂越来越引起研究者们的注意,并且已有多种多金属氧酸盐被设计为水氧化催化剂. 本文详细介绍了各种不同过渡金属取代的多金属氧酸盐水氧化催化剂的研究进展. 相似文献
28.
采用循环伏安法(Cyclic Voltammetry,CV)在碱性条件下电解石墨棒,得到水溶性的荧光碳量子点. 通过透射电子显微镜(TEM)、拉曼光谱(Raman spectrum)、原子力显微镜(AFM)对所制备的碳量子点进行形貌及结构表征,发现该碳量子点由1~4层石墨烯片层堆积形成,粒径在19 nm左右,厚度在1 nm左右. 通过荧光光谱(PL)、紫外可见吸收光谱(UV-vis)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)对所制备的碳量子点进行性质测定,发现该碳量子点在400和525 nm处有两个荧光发射峰,且通过控制扫描周数可以调节两个发射峰的相对强度,从而调控碳量子点的荧光颜色:随着扫描周数的增加,400 nm处发射峰的相对强度逐渐减小,而525 nm处发射峰的相对强度逐渐增大,两个荧光发射峰分别与碳量子点的π-π共轭体系和含氧官能团的n-π共轭体系有关. 相似文献
29.
New diterpenoid glucosides from Siegesbeckia pubescens 总被引:5,自引:0,他引:5
Jiang XIONG Qi Duan JIN Yun Long XU* Kunming Institute of Botany The Chinese Academy of Sciences Kunming 《中国化学快报》2001,(1)
Plants of the genus Siegesbeckia are annual herbs widely distributed in tropical and temperate zones and they are used as a traditional medicine to treat rheumatic arthritis, hypertension, malaria, neurasthenia and snake-bite in China. In previous papers, we reported on five new ent-kaurane and ent-pimarane diterpenoids, siegesbeckioside, siegesbeckiol and siegesbeckic acid1, orientalin A and B, and eight know compounds2,3. The present paper describes the isolation and structural elucidation … 相似文献
30.
1 INTRODUCTIONHeterometalpolynuclearcomplexeshavebeenthesubjectofmanyrecentstudiestoelucidatethemechanismofspincouplingbetweenthemetalions〔1,2〕,mimickingtheactivesiteofsomemetalenzymescontainingdissimilarmetalions,suchascytochromeoxidaseandsuperoxi… 相似文献